Re: [PATCH v2 01/12] [media] dvb-frontends/stv0367: add flag to make i2c_gatectrl optional

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



Am 24.03.2017 um 19:23 schrieb Daniel Scheller:
> From: Daniel Scheller <d.scheller@xxxxxxx>
> 
> Some hardware and bridges (namely ddbridge) require that tuner access is
> limited to one concurrent access and wrap i2c gate control with a
> mutex_lock when attaching frontends. According to vendor information, this
> is required as concurrent tuner reconfiguration can interfere each other
> and at worst cause tuning fails or bad reception quality.
> 
> If the demod driver does gate_ctrl before setting up tuner parameters, and
> the tuner does another I2C enable, it will deadlock forever when gate_ctrl
> is wrapped into the mutex_lock. This adds a flag and a conditional before
> triggering gate_ctrl in the demodulator driver.
> 

If I get this right, the complete call to i2c_gate_ctrl should be disabled.
Why not just overwrite the function-pointer i2c_gate_ctrl with NULL in
the relevant attach function (stv0367ddb_attach) or not define it in
stv0367ddb_ops?

That should have exactly the same effect.

Regards
Matthias




[Index of Archives]     [Linux Input]     [Video for Linux]     [Gstreamer Embedded]     [Mplayer Users]     [Linux USB Devel]     [Linux Audio Users]     [Linux Kernel]     [Linux SCSI]     [Yosemite Backpacking]
  Powered by Linux